PURPOSE: The Imaging Core will have 2 service functions. The first function is to provide technical support for state-of-the-art morphological methods. The second function is to collect and evaluate human tissue from autopsies, surgical resections and transplant procedures. 1. To provide technical expertise for state-of-the-art morphological methods. These methods include routine and specialized quantitative histology and electron microscopy, immunohistochemistry, and in situ hybridization. We have considerable expertise with in vivo experimental animal studies, in vivo experiments, and human tissue analyses. 2. To collect human tissues from autopsies, surgical resections and transplant procedures. The second function of the Imaging Core is to exploit the human tissue bank that Dr. Albertine established, with the invaluable assistance of Drs. Zimmerman. Michael and McIntyre. Such studies of the human lung in the ARDS are desperately needed to correlate with measurements of factors in bronchoalveolar lavage and plasma samples and to use as a "gold standard" for immunohistochemical and other studies in animal models of acute lung injury, as recognized by others (Pittet et al., 1997). We are particularly excited by the future plan of extending the analysis beyond the immediate goals of the specific projects, once the inflammatory phenotype of in situ endothelial cells has been defined, to analysis of the display of signaling factors, surface adhesion molecules, and other key variable sin other cell types in the milieu of the inflamed lung in ARDS. One of the exciting future plans is to share our human tissue bank with other SCOR programs, such as we are planning with Dr. Hudson's SCOR group in Seattle. SIGNIFICANCE: The contributions of the Imaging Core will substantially improve our understanding of dysregulated cell-cell interactions and intercellular signaling at different stages of the ARDS (e.g., early versus late injury, and injury versus repair).